How to disable activity sharing with Siri?
To disable activity sharing
1. Open the Bigin app on your iPad.
2. Tap on Settings 
at the bottom right of the screen.
Under "Manage Privacy", you can find the title "Privacy & Security".
3. Tap on Privacy & Security > Share Activities with Siri.
4. Tap the toggle switch 
to disable activity sharing with Siri.
Info: Once you've disabled activity sharing, your Bigin app usage pattern will stop being shared with Apple.